Apparant overdue account

I cancelled my telkom line at the Menlyn Telkom store and was very relieved the process was quick.<br> <br> However a few months down the line i was still getting invoices from telkom, i called the call centre after a quite normal 40 minute wait, only to find out the line was not cancelled and I was told that this was also common that if you cancelled your line in store, it actually wasnt cancelled.<br> <br> She then said that she backdated my cancellation and gave me a reference ***A on the 17/06/2015.<br> Nothing has happened, telkom sends me now sms's asking for my which i will not pay as i dont owe it.<br> <br> Please can someone at Telkom help me with this issue.